Lower tumbler and ladder end for elevator-dredges.



'PATENTED SEPT. 13, 1904. S. L. G. KNOX 6; W. FERRIS.

LOWER TUMBLER AND LADDER END FOR ELEVATOR DREDGES. APPLIOATION TILEDJAN. 21. 1904.

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No. 770,011. 4 PATENTED SEPT. 18, 1904. S. L. G. KNOX & W. FERRIS. LOWERTUMBLER AND LADDER END FOR ELEVATOR DREDGES.

APPLICATION FILED JAN. 21, 1904.

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I L'vi- 1- I UNITED STATES Patented September 13, 1904,

PATENT OEETEE,

SAMUEL LIPPINOOTT GRISWOLD KNOX, OE MILIVAUKEE, AND ALTER FERRIS, OFSOUTH MILWAUKEE, WVISOONSIN, ASSIGNORS TO THE BUOYRUS COMPANY, OF SOUTHMILWVAUKEE, WVISOONSIN, A CORPO- RATION OF WISCONSIN.

LOWER TUIVIBLER AND LADDER END FOR ELEVATOR-DREDGES.

SPECIFICATION forming part of Letters Patent No. 770,011, datedSeptember 13, 1904.

Application filed January 21, 1904. Serial No. 190,001x (No model.)

To (ZZZ whom it Huty concern:

Be it known that we, SAMUEL LIPPINCOTT GRIswoLD KNOX, residing in thecity of Milwaukee, and WALTER FERRIs, residing in the city of SouthMilwaukee, county of Milwaukee, lVisconsin, both citizens of the UnitedStates, have invented certain new and useful Improvements in LowerTumblers and Ladder Ends for Elevator-Dredges; and we do hereby declarethe following to be afull, clear, and exact description of theinvention, such as will enable others skilled in the art to which itappertains to make and use the same.

Our invention relates to certain new and useful improvements in lowertumbler mechanism for elevator-dredges; and it consists in the detailsof construction and the combinations of parts hereinafter described, andillustrated in the accompanying drawings, in which Figure 1 is a sideelevation of the lower end of a dredge-ladder supporting the lowertumbler including our improvements. Fig. 2 is a transverse section ofthe same.

In the operation of elevator dredging-machines the inclined ladder orgirder, which is hinged at its upper end to a stationary structure orboat, is provided at its respective ends with rotating tumblers orchain-wheels driven from a suitable source of power, which wheels carryan endless chain having dredging-buckets attached thereto. The lower endof the ladder is lowered to the river-bottom, and the dredging-bucketsdig or scrape out the mate rial as they pass around the lower tumbler.The lower end of the ladder is forked in order to support thetumbler-shaft, one arm of the fork passing down each side of the tumblerbeyond the main body of the ladder and serves to support one of thetumbler-shaft bearings. As heretofore constructed the ladder loses muchof its strength at the beginning of this fork, where it is virtually cutin two to accommodate the tumbler, and from this point to the extremelower end of the fork-section it is very weak laterally. The dredge isanchored so that it cannot back off from the I terioration of themechanism supported thereby. The lower tumbler is constantly running ain muddy water, which carries in suspension a large amount of grit orsand, which works into the bearings upon which the tumbler ro- 6o tatesand cuts them out very rapidly. Various devices have heretofore beenemployed in the attempt to render these bearings waterproof, or at leastgrit-proof, to prevent this latter difficulty; but so far as we areaware none of these devices have accomplished the desired object. Theprimary cause of the difficulty aforesaid arises from the springing ofthe ladder ends under the strain of the breasting-rope, as abovedescribed, the effect 7 of which is to pull the ladder ends apartsufficiently to loosen the rubber backing or other material and permitthe water and grit to gain access to the bearings. In addition to theseinherent faults of former tumbler constructions it has been found verydiflicult in practice to keep the rubber rings orfibrous packing of thelower tumbler from being torn out by small stones, which are carried inand ground against the packing by the rotation of 30 the tumbler.

The object of our invention is to overcome the several diflicultiesabove mentioned which are met in former tumbler constructions and toprovide a combination of elements which 5 will produce a much strongerfork for the lower tumbler and a grit-proof bearing for the latter soconstructed and arranged that while the parts maybe readily removed orreplaced, should occasion demand, the durability and 9 efliciency of theapparatus is greatly increased.

Referring to the drawings, a indicates the tumbler, which preferablyconsists of two sections f. f, is rigidly secured to a hollow shaft 0,which is supported in journal-boxes g g, mounted in recesses in therespective brackets b. To facilitate the assembly and adjustment of themembers of the tumbler, the brackets 6 Z) are provided with removablecaps cZ cl, which are secured to the brackets by means of bolts .9passing through lugs on the brackets and caps, respectively. It will benoted that the portion of the bracket which forms the bearing for thetumbler-shaft and the cooperating cap each constitutes a generallysemicylindrically shaped shell having its edge which meets .thecooperating part accurately milled to form a water-tight joint, and thetwo parts when assembled form a hollow chamber or cavity in which thecorresponding journal-box g is mounted; Each of said journal-boxes g,which conforms generally to the interior contour of the recess in thebracket, is provided with a peripheral bearing surface or ridge 6, whichengages a corresponding groove or depression in the interior of saidchamber to permit the journal-box to have a slight rocking movement toaccommodate any deviation of the shaft from its true position due tostrain on the mechanism. In order to hold the bearingbrackets whichconstitute the fork of the ladder at a fixed distance apart, a tie-rod7c is passed through the hollow shaft 0 and is provided at itsrespective ends with head portions, which are secured to the respectivebrackets. In the particular form of the invention shown these headportions consist of flanges or bosses H, which accurately fit intocircular recesses, one half of each of said recesses being formed in thelower face of bracket 7) and the other in the contiguous face of cap (Z,so that when the parts are assembled the ends of the tie-rod are rigidlylocked between the bracket and cap sections and serve to prevent thelegs of the fork from moving toward or from each other. It is to beobserved, of course, that any other suitable form of connection betweenthe tie-rod ends and the fork sides could be employed. For example, the

ends of the rod could be grooved to engage corresponding ribs in therecesses of the fork sides.

A rubber packing-ring n is mounted between the contiguous faces of eachfork member and the tumbler and serves to exclude water and grit fromthe bearings. This ring is preferably formed as a folded rubber gasketwith a strengthening-wire and is clamped firmly in place when the forkmembers are drawn up by the tie-rod. A guard-ring 0 is mounted outsideof the packing-ring and is preferably formed of two pieces, one securedto the bracket 7) and the other to the cap (Z, and

shaft to the opposite bracket.

serves to exclude sand or small stones which would work in between thetumbler and the adjacent fork member as the tumbler rotates. Thisguard-ring is secured in position by screws p and fits accurately in thespace between the fork member and the adjacent tumbler-face.

Lubricating oil or grease is supplied to thetumbler-bearings by pipes qq, connected to a source of supply on the upper end of theladder or uponthe dredge-boat above the surface of the water. Each of said pipescommunicates with the space around one of the journal-boxes g and thenceby oil-holes r and suitable grooves in the bearing-box to thetumbler-shaft.

The advantages incident to the above construction are in part asfollows: The tie-bolt 10 serves to accurately and rigidly hold therespective sides of the ladder-fork at a fixed distance apart, and anystrain that is received by one member of the fork is immediatelycommunicated to the opposite member thereof, thus practically doublingthe strength of the fork to resist bending strains. This tying togetherof the fork members prevents the bearings from being thrown much out ofline, and consequently prevents the opening of gaps between the sides ofthe tumbler and the fork members, which would permit grit and water topass into the bearings. The annular bearing-surface i on each of thejournal-boxes g serves to support said journal-box, which carrice theweight of the tumbler and takes up the diggingstrains and permits aslight change in the alinement of the bearings as the lad der end isdeflected as a whole under varying loads, and the end surface m of eachof said boxes, which is in contact with the bottom of the recess in thebracket 6, serves to transmit lateral thrust strains through thetumbler- The arrangement of the bearings whereby the tumblershaft issupported at its extreme ends distributes the end thrust caused byforcing the tumbler into the gravel most advantageously at points wherethe lubrication is best and at the greatest possible distance from thosepoints where water or grit would tend to seep in in spite of the bestpacking.

Having thus described our invention, what we claim, and desire tosecure, is

1. In a lower tumbler mechanism for dredging-machines and the like, thecombination of a-hollow rotating tumbler-shaft, brackets in which saidshaft is supported, and a tie-rod passing through said shaft and securedto said brackets to hold the latter at a fixed distance apart. 7

2. In a lower tumbler mechanism for dredging-machines and the like, thecombination of a hollow tumbler-shaft, brackets in which said shaft issupported, removable caps on said brackets, and a tie-rod passingthrough said shaft and secured at its ends between the brackets andcaps, whereby the tie-rod is rigidly held in place and the brackets areheld at a fixed distance apart.

3. In a lower tumbler mechanism for dredging-machines and the like, thecombination of a hollow tumbler-shaft, brackets embracing one half ofthe shaft ends, removable caps embracing the other half of said shaftends, and a tie-rod passing through said shaft, said tie-rod havingheads on its ends engaging mating recesses formed in the contiguousfaces of the respective brackets and caps, whereby the tie-rod isrigidly held in place and the brackets are held at a fixed distanceapart.

4. In a lower tumbler mechanism for dredging-machines and the like, thecombination of a hollow tumbler-shaft, brackets in which said shaft issupported, a tie-rod passing through said shaft and secured to saidbrackets to hold the latter at a fixed distance apart, and a removablejournal-box for said shaft supported in each of said brackets.

5. In a lower tumbler mechanism for dredging-machines and the like, thecombination of a hollow tumbler-shaft, brackets in which said shaft issupported, a tie-rod passing through said shaft and secured to saidbrackets to hold the latter at a fixed distance apart, and a removablejournal-box for said shaft supported in each of said brackets, each ofsaid journalboxes having a rocking bearing in its supporting-bracket toaccommodate any deviation of the shaft under strain.

6. In a lower tumbler mechanism for dredging-machines and the like, thecombination of a hollow tumbler-shaft, a tumbler mounted thereon,brackets in which said tumbler-shaft is supported, a tie-rod passingthrough said shaft and secured to said brackets to hold the latter at afixed distance apart, and packingrings held between the adjacent facesof the tumbler and the brackets.

7. In a lower tumbler mechanism for dredging-machines and the like, thecombination of a hollow tumbler-shaft, a tumbler mounted thereon,brackets in which said tumbler-shaft is supported, a tie-rod passingthrough said shaft and secured to said brackets to hold the latter at afixed distance apart, packing-rings held between the adjacent faces ofthe tumbler and the brackets, and a guard-ring secured in positionbetween the tumbler and the brackets outside of the packing-ring.

In testimony whereof we aflix our signatures in presence of twowitnesses.

SAMUEL LIPPINCOTT GRISWOLD KNOX. WALTER FERRIS Witnesses:

HARRY B. HAYDEN, PAUL C. Bone.

